Table 7. Average class size in public primary schools, middle schools, high schools, and schools with combined grades, by classroom type and state: 2011–12

Primary schools

Middle schools

High schools

Combined grade schools

State

Average class
size for teachers in self-contained classes

Average class size for teachers in departmentalized instruction

Average class
size for teachers in self-contained classes

Average class size for teachers in departmentalized instruction

Average class
size for teachers in self-contained classes

Average class size for teachers in departmentalized instruction

Average class
size for teachers in self-contained classes

Average class size for teachers in departmentalized instruction

United States

21.6

26.2

16.7

25.5

17.7

24.2

16.6

19.0

Alabama

19.4

29.4

11.0

28.4

29.4

!

23.0

17.0

19.0

Alaska

21.1

17.4

4.0

21.8

14.7

!

20.3

13.4

10.2

Arizona

24.5

25.3

10.9

26.2

23.5

25.9

20.1

19.5

Arkansas

20.4

22.8

13.9

23.1

19.9

20.5

19.5

19.8

California

25.4

28.2

23.4

30.7

20.6

30.0

19.0

21.9

Colorado

23.3

26.1

16.6

26.1

16.7

!

27.9

17.3

22.1

Connecticut

20.1

22.2

17.8

22.2

17.4

!

19.9

‡

19.1

Delaware

21.1

31.3

‡

25.3

16.0

23.6

6.2

17.0

District of Columbia

‡

‡

‡

‡

‡

‡

‡

‡

Florida

‡

‡

‡

‡

‡

‡

‡

‡

Georgia

21.2

24.3

14.8

24.4

7.2

!

25.4

13.7

17.6

Hawaii

‡

‡

‡

‡

‡

‡

‡

‡

Idaho

25.1

27.8

19.3

25.9

15.8

22.2

18.3

19.1

Illinois

23.5

24.8

14.4

24.9

10.8

26.4

14.7

18.5

Indiana

21.7

35.1

18.3

25.8

14.4

23.6

17.0

18.9

Iowa

20.9

21.5

15.6

27.8

12.2

22.8

16.0

21.0

Kansas

20.7

20.6

13.6

24.0

20.7

19.7

17.5

16.0

Kentucky

23.7

23.5

7.3

26.9

18.7

23.6

15.1

18.0

Louisiana

19.4

21.3

8.6

!

23.4

‡

22.5

17.7

16.7

Maine

17.8

18.4

!

12.3

21.6

16.1

16.7

9.5

13.4

Maryland

‡

‡

‡

‡

‡

‡

‡

‡

Massachusetts

20.1

32.2

16.5

25.0

15.4

22.0

19.2

!

19.3

Michigan

25.7

36.0

25.2

28.0

27.8

27.3

13.8

20.4

Minnesota

23.7

31.0

23.5

!

29.5

21.9

27.0

16.8

23.1

Mississippi

22.1

25.5

‡

22.5

9.3

19.7

15.2

17.0

Missouri

20.7

23.5

18.4

25.9

14.1

21.8

17.1

19.5

Montana

20.5

17.7

16.4

24.0

19.1

20.6

12.8

12.5

Nebraska

19.0

18.3

14.6

25.6

17.4

21.4

15.2

16.5

Nevada

26.1

54.4

!

10.2

!

31.8

23.9

!

31.2

13.4

!

25.4

New Hampshire

21.2

16.6

20.0

!

23.5

15.1

!

19.7

10.9

13.0

New Jersey

19.0

20.4

10.8

24.6

12.7

21.9

7.9

20.4

New Mexico

20.5

19.8

!

13.5

!

23.2

27.9

!

22.0

14.4

13.3

New York

21.5

25.9

13.8

24.5

17.4

22.5

12.9

!

19.2

North Carolina

19.8

32.8

14.9

25.5

9.9

24.3

19.7

19.7

North Dakota

19.3

24.7

10.9

20.9

26.1

!

18.4

14.5

14.2

Ohio

21.8

24.0

17.1

25.6

19.3

23.6

19.1

20.2

Oklahoma

21.1

27.5

16.0

25.4

15.9

19.8

17.5

17.7

Oregon

26.7

24.1

29.2

28.8

16.2

28.1

18.2

15.3

Pennsylvania

22.6

28.1

13.0

24.9

16.0

21.4

27.2

!

20.7

Rhode Island

‡

‡

‡

‡

‡

‡

‡

‡

South Carolina

19.4

28.4

8.6

23.9

9.5

22.4

20.0

15.2

South Dakota

21.7

22.3

‡

24.8

18.6

20.9

16.7

15.8

Tennessee

17.8

31.4

15.9

!

25.4

18.1

!

24.6

18.5

20.5

Texas

18.6

26.4

13.4

24.4

18.0

!

23.6

15.1

16.8

Utah

27.6

8.3

19.6

29.4

25.4

29.0

21.9

28.6

!

Vermont

16.7

19.3

16.8

20.9

12.7

17.7

14.2

10.9

Virginia

20.4

28.9

15.6

!

22.3

14.3

22.8

13.7

!

10.3

Washington

23.9

37.0

29.1

27.0

28.5

27.0

17.7

15.4

West Virginia

19.2

27.8

9.1

!

23.5

8.9

!

19.8

19.8

!

20.3

Wisconsin

20.8

35.2

!

24.7

28.4

15.7

23.2

21.6

!

19.9

Wyoming

17.4

‡

11.9

21.3

8.5

17.8

13.4

12.9

! Interpret data with caution. The coefficient of variation (CV) for this estimate is between 30 percent and 50 percent (i.e., the standard error is at least 30 percent and less than 50 percent of the estimate).

‡ Reporting standards not met. The coefficient of variation (CV) for this estimate is 50 percent or greater (i.e., the standard error is 50 percent or more of the estimate) or the response rate is below 50 percent.

NOTE: Self–contained classes are defined as instruction to the same group of students all or most of the day in multiple subjects, and departmentalized instruction is defined as instruction to several classes of different students most or all of the day in one or more subjects. Among all public school teachers, 27 percent teach self–contained classes in primary schools, 1 percent in middle schools, 1 percent in high schools, and 1 percent in combined schools; 7 percent teach departmentalized classes in primary schools, 14 percent in middle schools, 25 percent in high schools, and 4 percent in combined schools; 14 percent teach other types of classes, such as elementary subject specialist classes, team–taught classes, and "pull–out" or "push–in" classes in primary schools, 3 percent in middle schools, 2 percent in high schools, and 1 percent in combined schools.